An Icelandic volcano could trigger a 'major disaster' and erupt at any second, a scientist has warned. Nicknamed the 'Gateway to Hell', the Hekla volcano is located in the southern part of the country and has been quiet for sixteen years.

New data has revealed it is building up magma with its internal pressure currently higher than before its last two previous eruptions. Around 20 to 30 passenger planes fly over the volcano every day, and an expert says these could in danger from the resulting ash.

However, scientists claim an ash cloud, if it appears, will not be as large or devastating as the one spewed out from Eyjafjallajökull in 2010. The impact is expected to be localised, with no flights expected to be grounded in the UK and western Europe. The volcano has erupted approximately once every 10 years, from 1970 to 2000, but has remained dormant ever since.

University of Iceland Geophysics Professor Páll Einarsson told Icelandic news agency Visir people should stop visiting the volcano, which is a popular tourist destination, due to an increased risk of eruption. 'Hekla is a dangerous volcano,' said Professor Einarsson.

'We could be looking at a major disaster when the next eruption begins if we are not careful.' The 4,892-foot (1,491-metre) mountain last erupted in February 2000.

'Hekla is ready – at any moment,' Professor Einarsson said. 'There are also 20-30 planes full of passengers flying right over the top of Hekla every day,' he warns.

Nicknamed the 'Gateway to Hell', the Hekla volcano
is located in the southern part of the country (location pictured)
and has been quiet for sixteen years

But Professor Einarsson told MailOnline this was not an unusual situation. 'Let me assure you, there is nothing unusual going on with our volcanoes at this time, at least nothing that we are aware of,' he said. 'Business as usual.'

At the time of writing, the Icelandic Met Office had not responded to MailOnline's request for comment on the likelihood of Helka erupting. 'Eruptions are relatively frequent in Iceland. In the last 45 years there have been 22 confirmed eruptions, so on the average, about one eruption every two years,' Professor Einarsson added.

'Most of these are small and do not cause much harm or damage. Among Icelanders they are regarded as events of public entertainment.'

'Hekla is one of the most frequently active volcanoes in Iceland and since 1947 it had several rather frequent eruptions (1947 followed by 1970, 1980, 1991 and 2000),' Dr Evgenia Ilyinskaya, research fellow from the University of Leeds who was worked on the Hekla volcano extensively, told MailOnline.

'However, this “10 year pattern” is unusual if we look at a longer timescale,' she said. 'Before 1947 Hekla erupted much less frequently - roughly speaking once a century - especially if we look only at explosive ash-producing eruptions.

'It is not known if the frequent eruptions 1947-2000 will continue or if Hekla has gone into the same pattern as before 1947 and there will be a much longer pause until the next eruption.'

Professor Einarsson also expressed similar concerns of the volcano erupting in March 2014. 'At the moment Hekla is quiet, there are no earthquakes which signal that eruption may happen soon, Dr Ilyinskaya added.

'Pall Einarsson told the news that the volcano is inflated above the level that it was known to have reached before the last eruption, which is correct. What is not known is how long Hekla is able to stay inflated – it might be a short or a long period of time.

'For these reasons I fully agree with Pall Einarsson that Hekla is a dangerous place for tourists – we don’t know how much warning the volcano will give but it’s likely to be relatively short. It is difficult or even impossible to evacuate groups of people from the top of Hekla. I support Pall’s suggestion that people should not be going up to the top of Hekla for sightseeing.'

Even if it does erupt, there is not a high risk of an ash cloud disrupting travel across Europe, however. 'Based on the evidence from its recent eruptions, Hekla is very unlikely to produce an ash cloud anything like the one that Eyjafjallajökull produced in 2010,' Dr David McGarvie, a senior lecturer and expert in Icelandic volcanoes at the Open University, told MailOnline.

'The evidence shows that Hekla only produces large eruptions with disruptive ash clouds after gaps of centuries between eruptions – not decades. And Hekla last erupted only c.16 years ago.' Since the disaster in 2010, methods for detecting ash clouds have also improved. This means even if the Hekla volcano releases a similar ash cloud, history would not repeat itself.

'In any case, changes to ash detection plus changes to the guidelines governing aircraft flying when volcanic ash is in the sky mean that an identical eruption to Eyjafjallajökull 2010 would now only result in c.30 per cent of the flight cancellations etc that we saw in 2010,' Dr McGarvie added.

'In summary, unless something extremely unexpected happens at Hekla its next eruption will be a small and localised one like the last few. 'And will result in minor amounts of ash in the sky, little if any of which will reach the UK and western Europe.'

Dr Ilyinskaya agreed: 'Because we had a eruption in Hekla only 16 years ago the next eruption is highly likely to be small. We would need a repose of about 100 years to produce anything similar to Eyjafjallajökull in 2010.'

The Eyjafjallajökull eruption grounded flights across the UK and Europe in April 2010 after a cloud of volcanic ash which could damage jet engines drifted across the area. Eruptions at the Eyjafjallajokull volcano thrust torrents of molten rock through the shattered ice sheets in the mountain crater, spewing a towering wall of ash, dust and steam high into the air.

Seismic activity started at the end of 2009 and gradually increased in intensity until 20 March 2010, when a small eruption started. From 14 April 2010, the eruption entered a second phase and created an ash cloud that led to the closure of most of the European airspace from 15 until 20 April 2010.

As a consequence of this, a very high proportion of flights within, to, and from Europe were cancelled, creating the highest level of air travel disruption since the Second World War. Volcano watchers have anticipated a new eruption at Hekla since 2006, when tiny earthquakes and surface swelling first hinted that new magma had appeared. Media reports warned of similar surface swelling at Hekla in 2011, 2013 and 2014, without a subsequent eruption.

The two volcanoes also have different erupting styles, Dr Ilyinskaya told MailOnline. 'Eyjafjallajökull had a very prolonged eruption, with ash being continuously produced in several episodes over 6 weeks. Hekla emits all of its ash in a matter of hours so there is a better chance that the ash will "blow over“ much quicker than in the 2010 eruption.'